Periodic safety review

Safety Series No. 50-SG-012 Periodic Safety Review of Operational Nuclear Power Plants (1994). 

MS I programmes will identify and monitor ageing mechanisms of SSCs, which should then be reviewed in the formal periodic safety reviews conducted for the plant (see Ref. [7]). The periodic safety reviews may identify needs for additional or enhanced maintenance or surveillance, and a review or enhanc ent of the MS l programme to take such needs into account should be considered. 

INTERNATIONAL ATOMIC ENERGY AGENCY, Periodic Safety Review of Nuclear Power Plants, Safety Standards Series No. NS-G-2.10, IAEA, Vienna (in preparation). 

AR19 Periodic safety review of nuclear power plants, NS-G-2.10, 12 September 2003. 

As a part of the (periodic) safety reviews (BMU 1996) of the German nuclear power plants, the protection against external hazards has to be re-assessed. According to the guidance on probabilistic safety reviews (BMU 2005) and following the international state-of-the-art (IAEA 2008) the deterministic assessments have to be supplemented by probabilistic analyses. But up to now, the spectrum of external... 

The Nil had become concerned with the performance of the two licensees because of a variety of problems. These included the diminished quality of recent Periodic Safety Review (PSR) submissions, the foiline of the licensees to deliver promised PSR modifications, their failure to make long-term commitments in areas such as research, and the decreased quality of some technical advice. The Nil had followed up on these problems individually, but the frequency and consistency of the observed problems started to suggest a systemic underlying weakness arising from the restructuring. 

This Safety Guide supplements the IAEA Safety Fundamentals publication The Safety of Nuclear Installations [1] and the Safety Requirements publication Safety of Nuclear Power Plants Operation [2]. It supersedes the Safety Guide issued as Safety Series No. 50-SG-O12, Periodic Safety Review of Operational Nuclear Power Plants, in 1994. 

Periodic Safety Review of Nuclear Power Plants... 

PERIODIC SAFETY REVIEW OF NUCLEAR POWER PLANTS... 

Section 2 discusses the safety implications of the design process and the relevant acceptance criteria required for different safety classes. In Section 3 the design principles for the achievement of the protection objective are recommended and the concept of periodic safety review is discussed in relation to the design issues. Guidance on an appropriate selection of methods for seismic qualification is provided in Section 4, recommendations for qualification by analysis are provided in Section 5, and qualification by test and... 

The collection and analysis of data should be carried out on a regular basis to support the periodic safety review of the plant. 

The structure corresponds to the logical sequence of the analyses required for the definition of the design basis flood from the site survey stage up to the definition of the design basis and the periodic safety review on the basis of monitoring results. In particular. Section 3 deals with the preliminary investigation for site selection and Section 4 with final data collection for the site assessment up to the definition of the parameters (and probabilities, if required) for the cause of initiation of the flood (precipitation, tornadoes, earthquake and dam failures). 

Some safety margin should be taken into consideration in the design of a nuclear power plant. If periodic safety reviews are conducted, such a margin may refer to the interval between two consecutive reviews. K the entire plant lifetime is considered, the following generally agreed estimated variations in parameters may be considered ... 

The seismic design of equipment in German NPPs is based on the KTA 2201. Re-evaluation is carried out within the framework of the periodic safety reviews taking into account the revised KTA 2201.1 and KTA 2201.3/4. 

Regulatory body is considering to implement 5-year PSR (Periodic Safety Review) to identify any weakness. 

In a periodical safety review, fatigue evaluation is performed on reactor pressure vessel using actual number of transients. 

The adequacy of the design had been confirmed in the Periodical Safety Review. 

In Sweden, the regulatory body requires that a fire hazards analysis and a flooding assessment be a part of the second round of the periodic safety reviews, the ASAR 90 programme. These where performed by the utilities in the 90s. 

Guidelines for accident analysis of WWER nuclear power plants, IAEA, EBP-WWER-01, 1995. INTERNATIONAL ATOMIC ENERGY AGENCY, Periodic safety review of operational nuclear power plants A Safety Guide, Safety Series No. 50-SG-O12, IAEA, Vienna (1994). INTERNATIONAL ATOMIC ENERGY AGENCY, Ranking of safety issues for WWER-440 model 230 nuclear power plants, IAEA-TECDOC-640, Vienna (1992). 

The completeness of the definition of hazards due to DBEEs may be affected by possible changes that have occurred in both the industrial environment and the transport environment since the siting process was followed, and also in natural hazards (e.g. because of climate changes), as foreseen in the Safety Requirements for Design [1]. Such changes are mainly considered in periodic safety reviews [13]. 

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